Watch Katy Perry & Kanye West Perform "E.T." on 'American Idol'

With all the special effects, it's no wonder Katy Perry's performance on American Idol featuring Kanye West was pre-taped. Katy transformed herself into an alien and performed her #1 hit song, "E.T" with Kanye on Thursday.

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The performance kicked off with Kanye on a video screen, but he later appeared in the flesh with Katy on stage.

As for Katy, she made her appearance on stage by being carried by three "alien" dancers, MTV News reports. In true Katy style, her skin-tight white bodysuit featured pink LED lights.

What did you think of Katy and Kanye's futuristic performance?

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Watch the performance below!